Unit dose dispensing mechanisms

Abstract

Mechanisms for dispensing items such as medications and medical supplies. Different mechanisms may be tailored to dispensing different kinds of items, for example medications in single dose packages, vials, syringes, or other similarly-shaped items. The dispensers may be placed in a dispensing unit that includes a lockable restock drawer and a dispense drawer into which items are dispensed by the dispensing mechanisms. The various kinds of dispensing mechanisms may be installed in the restock drawer in any workable proportion and arrangement. The dispensing mechanisms include multiple sensing technologies for tracking and inventory of items and for accurate sensing of items as they are dispensed.

What is claimed is: 
     
       1. A dispensing mechanism, comprising:
 a dispenser; 
 a cassette that stores a supply of items to be dispensed; 
 a connector for receiving electrical signals from a cabinet in which the dispensing mechanism is installed, wherein the connecter enables the dispensing mechanism to be removably electrically connected to the cabinet; 
 an actuator that moves in response to the electrical signals; 
 a housing in the cassette for storing the items to be dispensed, the housing defining an opening at a bottom of the housing, wherein items are to be dispensed through the opening, and wherein the housing is configured such that items feed by gravity toward the opening as items are dispensed; 
 a moveable slide driven by the actuator, the moveable slide having a slot through the movable slide, wherein items to be dispensed fall one at a time into the slot; and 
 a spring that biases the slide into a default position in which the slot of the moveable slide is not aligned with the opening; 
 wherein when the slide is moved by the actuator, the slide translates against the action of the spring into a position in which the slot in the slide aligns with the opening, allowing a single item in the slot to fall through the opening to be dispensed; 
 wherein the connector and the actuator are comprised in the dispenser, and the slide and the spring are comprised in the cassette; 
 wherein the dispenser and the cassette are separable; 
 and wherein the cassette does not include any active electrical components. 
 
     
     
       2. The dispensing mechanism of  claim 1 , wherein the actuator is selected from the group consisting of a motor, a solenoid, and a memory metal. 
     
     
       3. The dispensing mechanism of  claim 1 , wherein the items in the housing are visible from outside the housing through a wall of the housing. 
     
     
       4. The dispensing mechanism of  claim 1 , further comprising:
 one or more light emitters positioned to form a light curtain below the opening; and 
 one or more receivers that detect light from the one or more light emitters, the one or more light emitters and the one or more receivers positioned such that the light emitted by at least one of the one or more light emitters is interrupted by the passage of a dispensed item through the opening. 
 
     
     
       5. The dispensing mechanism of  claim 4 , wherein the one or more receivers detect light reflected from a far wall of the opening or from an item being dispensed. 
     
     
       6. The dispensing mechanism of  claim 4 , wherein the one or more receivers detect light received directly from one or more of the one or more light emitters. 
     
     
       7. The dispensing mechanism of  claim 1 , wherein:
 the cassette includes a wirelessly-readable memory; and 
 the dispenser includes a reader for reading the wirelessly-readable memory. 
 
     
     
       8. The dispensing mechanism of  claim 1 , wherein the dispenser is mechanically removably securable to the cabinet. 
     
     
       9. A dispensing mechanism, comprising:
 a dispenser; and 
 a cassette that stores a supply of items to be dispensed; 
 a connector for receiving electrical signals from a cabinet in which the dispensing mechanism is installed, wherein the connecter enables the dispensing mechanism to be removably electrically connected to the cabinet; 
 an actuator that moves in response to the electrical signals; 
 a housing in the cassette for storing the items to be dispensed, the housing defining an opening at a bottom of the housing, wherein items are to be dispensed through the opening, and wherein the housing is configured such that items feed by gravity toward the opening as items are dispensed; 
 a moveable slide driven by the actuator, the moveable slide having a slot through the movable slide, wherein items to be dispensed fall one at a time into the slot; and 
 a spring that biases the slide into a default position in which the slot of the moveable slide is not aligned with the opening; 
 wherein: 
 the connector and the actuator are comprised in the dispenser, and the slide and the spring are comprised in the cassette; 
 the dispenser and the cassette are separable; 
 the cassette does not include any active electrical components; 
 when the slide is moved by the actuator, the slide translates against the action of the spring into a position in which the slot in the slide aligns with the opening, allowing a single item in the slot to fall through the opening to be dispensed; and 
 the cassette further comprises a brake that is automatically engaged when the cassette is removed from the dispenser, the brake hindering movement of the slide when the brake is engaged. 
 
     
     
       10. The dispensing mechanism of  claim 9 , wherein the dispenser is mechanically removably securable to the cabinet. 
     
     
       11. A dispensing mechanism, comprising:
 a dispenser; and 
 a cassette that stores a supply of items to be dispensed; 
 a connector for receiving electrical signals from a cabinet in which the dispensing mechanism is installed, wherein the connecter enables the dispensing mechanism to be removably electrically connected to the cabinet; 
 an actuator that moves in response to the electrical signals; 
 a housing in the cassette for storing the items to be dispensed, the housing defining an opening at a bottom of the housing, wherein items are to be dispensed through the opening, and wherein the housing is configured such that items feed by gravity toward the opening as items are dispensed; 
 a moveable slide driven by the actuator, the moveable slide having a slot through the movable slide, wherein items to be dispensed fall one at a time into the slot; and 
 a spring that biases the slide into a default position in which the slot of the moveable slide is not aligned with the opening; 
 wherein when the slide is moved by the actuator, the slide translates against the action of the spring into a position in which the slot in the slide aligns with the opening, allowing a single item in the slot to fall through the opening to be dispensed; 
 wherein the connector and the actuator are comprised in the dispenser, and the slide and the spring are comprised in the cassette; 
 wherein the dispenser and the cassette are separable; 
 wherein the cassette does not include any active electrical components; 
 and wherein the housing defines a serpentine channel through which items feed by gravity toward the opening. 
 
     
     
       12. The dispensing mechanism of  claim 11 , wherein the dispenser is mechanically removably securable to the cabinet.